Closure latch



July 21, 1959 J. W. DORSAK ET AL CLOSURE LATCH 2 Sheets-Sheet 1 Filed Nov. 26, 1957 INVENTORS. JOHN W. .DORSAK All) BY THOMAS F. VAN DENBERG A TTORNEYS CLOSURE LATCH Application November 26, 1957, Serial No. 698,976-

7 Claims. (Cl. 292-87) This invention relates ingeneral to latching or fastening devices and more particularly to the class of latching devices used to detachably secure a closure, such as a nited States Patent movable door, unto a supportingflwall, cabinet, housing,

or the like.

. The latching device of the invention is especially adapted for securing a swingable door of an incubator in closed position, and it will be described in connection with such an environmental setting, although it will be understood that the latching device may be used in a great number of otherclosure assemblies.

Various types of latching devices are used to detachably secure what is known in the art as an incubator hand-hole door in closed position on the cabinet or housing portion of the incubator. A common typeof latch or fastener for such a purpose comprises a relatively small stamped metal pawl which is movably mounted in a stud assembly secured to the incubator housing. The pawl is adapted to extend through a slot in the stud assembly and. engage in overlapping relationship, an adjacent flange or web portion of the closure or door of the incubator, to hold the door in closed position. A spring is generally used to urge the pawl into interlocking relationship with the flange of the incubator door or closure and an externally accessible plunger or button member is usually provided in the outer or external end of the stud assembly for re tracting the pawl into the slot in the stud, to release the door for opening of the latter. Because of space and dimensional limitations, these prior art stud and pawl assemblies give a very small engagement of the pawl with the mating portion of the door, and therefore comparatively quickly wear out, become loose and inoperable, and thus do not effectively function to hold the door of the incubatorin closed position, thereby defeating or reducing the workability and useability of the incubator. Furthermore, after a relatively short period of use, the

spring of such a prior art latching device becomes fatigued, and either breaks or no longer pushes the pawl out far enough through the slot in the stud to make engagement with the mating door or closure, thereby resulting in an inoperable latch and incubator mechanism.

The present invention provides a spring-stud latching mechanism which eliminates the above discussed disadvantages of the prior art devices and which is comparatively simple in construction, positive in operation for holding the closure or door in closed position, readily and quickly manipulatable for releasing the door to open the latter, and which will retain its positive holding char-. acteristics after extended and repetitious use.

Accordingly it is an object of the invention to provide a latching device to hold a closure member such 2v as a door or the like, in closed position on a supporting part, such as a cabinet or housing, and one which is relatively simple and economical in construction, but which will operate eifectively after extended and repetitious use, to positively hold the closure member in closed or shut position.

Another object of the invention is to provide a device of thelatter mentioned type, which may be readily and quickly manipulated to release the latching device from coaction with the closure, thus permitting opening of the latter.

A more specific object of the invention is to provide a latching device for efiectively holding a closure member in closed position on a supporting part or housing, and wherein such device comprises a slotted stud member which is adapted to extend through an opening in the closure member, and a wire, spring-like holding member positioned in the slot in the stud and extending outwardly thereoffor holding engagement with a portion of the closure member, and wherein a portion of the holding member is externally accessible whereby it may be re tracted back into the slot to permit movement of the closure member to open position.

Other features and advantages of the invention will be apparent from a consideration of the following description taken in conjunction with the accompanying drawings wherein:

Fig. 1 is a fragmentary, sectioned, vertical plane view of an incubator cabinet with the door of the cabinet being held in closed position by the latching device of the invention in dot-dash lines the door of the incubator is shown removed from closed position.

Fig. 2 is an enlarged, partially sectioned, side elevation of a complete assembly of the spring-stud latching device of the invention.

Fig. 3 is a bottom plan view of the spring-stud mechanism of Fig. 2.

Fig. 4 is a vertical section taken generally along lines 44 of Fig. 2 looking in the direction of the arrows.

Referring to the drawings, the latching device 10, in the embodiment shown, broadly comprises a slotted shank portion 12 which is adapted to extend through an opening 13 in the closure or door member A'of the incubator mechanism, a spring-like or yieldable holding or catch member 14 which is movably disposed in the slot of the shank portion 12, and which projects outwardly thereof for engagement with a mating portion of the door A of the closure assembly to hold the door in closed or shut position, ashoulder or abutment portion 16 which is adapted for juxtapositioned relationship with the cabinet or supporting portion or part B of the incubator, and a threaded head portion 18 which is adapted to coact with a fastener, such as a nut 20, for securing the latching device to the incubator cabinet.

Shank portion 12 is slotted, as aforesaid, as at 22, longitudinally of the stud, to define lengthwise extending, stud finger sections 23 and 24. The leading end of the stud portion 12 is rounded or curved as at 26 to aid in feeding the shank portion through the opening 13 in door A of the incubator. In the embodiment shown, shank portion 12 is integrally secured to shoulder or abutment portion 16 and projects forwardly from the latter.

Shoulder portion 16, in the embodiment illustrated, is of hexagonal exterior configuration and has a transversely extending opening or passageway 28 (Fig. 2) extending completely therethrough.

Patented July 21, 1959" Passageway 28 is adapted to receive the base or leg section 30 of catch member 14 and mount the latter on the latching device 10. Leg section 30 preferably projects generally the full extent of passageway 28 in the shoulder portion 16, and thus provides substantial supporting contact between the shoulder portion and the catch member.

Leg portion 30 extends generally vertically downwardly a substantial amount from the lower extremity of shoulder portion 16 and then is bent rather sharply as at,32 to extend forwardly and upwardly to form comparatively long, diagonally extending body portion 34, which at its forward end projects into the slot 22 between finger sections 23 and 24 of the shank 12. From diagonal portion 34, the spring 14.is reversely bent in a smooth curve,

as at 36, to extend downwardly and generally diagonally rearwardly to form the hook or catch portion 38 of the holding spring member 14. The purpose and functioning of the rearwardly sloped configuration of hook portion 38 will hereinafter be more thoroughly discussed. At the lower extremity of portion 38, member 14 is bent rather sharply to extend forwardly and diagonally upwardly to form thrust or lift portion 40. Portion 40 is normally dis-' posed exteriorly of the slot 22 in shank 12 and is for the purpose of providing means for lifting or moving the catch member 14 out of holding coaction with the closure member A of the incubator, to permit opening the closure member. At its upper end, lift portion 40 is bent rearwardly toform a generally horizontally disposed girder or bridging portion 42. Portion 42 extends between lift portion 40 and the diagonal body portion 34, and rigidifies the catch and'lift portions 38 and 40 against flexure thereof during operation of the latching device. Catch portion 38, lift portion 40, and bridging portion 42 combine to form a generally triangular shaped head ele' ment 44 on spring member 14, with the inner end 46 of portion 42 engaging in frictional contact the curved configuration 36 of the spring (Fig. 2) thereby providing head element 44 with high strength characteristics and one which is not easily deformable.

The fastening device has an opening 48 extending generally axially therethrough commencing at the inner or right hand end of the latching device, as viewed in the drawings, and extending through the threaded portion 18 and shoulder portion 16, and opening into slot 22 in the shank 12. Opening 48 intersects with the transverse passageway 28 in shoulder portion 16. A pin or shaft 50 is adapted to be driven into opening 48 and em gage the leg section-30 of spring member 14 and deform the same as at 54 (Fig. 2) to positively lock the spring in proper position on shoulder section 16. Pin 50 is preferably of slightly greater cross-sectional area than the receiving opening 48 to insure that the pin will remain in assembled relationship in opening 48 to aid in holding leg section 30 of spring 14in assembled condition in passageway 28 in shoulder portion 16. Pin 50 is also-preferably of such length that it extends somewhat rearwardly of threaded section 18 when in assembled position (Fig. 2) to provide means for easy removal of the pin in the event of the need to replace the spring member 14.

When the spring 14 is mounted and secured in passageway 28 in the manner aforedescribed, the bend 32 in the spring member between leg section 30 and body section 34 is such that the head 44 of the spring element is urged downwardly or. outwardly of slot 22. In order to limit this downward or. outward movement of head portion 44 of the spring, the external surfaces of the lower edges of finger sections 23 and 24 of shank 12, adjacent the bottom extremity of slot 22, are prick punched or deformed asat. 56. Body section 34 adjacent the curved portion 36 of the spring member engages these deformed portions of the fingers, and thus prevents (further outward movement of head 44 .from slot 22. It will be apparent that the deformed portions 56 prevent movement of the spring in the wrong direction, as well as regulating the desired overlap between the head 44 of the vicinity of opening 13 therethrough,

4 spring and the associated mating portion of the closure member A, and thus prevent permanent injury or deformation to the spring in the event that inexperienced personnel attempt to force the catch member downwardly to open the incubator closure. Excess movement or flexure of the spring in the opposite or upward direction is prevented by movement of the spring head 44 and associated lift-portion 40 into the slot 22, thereby preventing deformation of the spring material beyond its elastic limit. The diagonal slope of lift portion 40 of the spring provides for its partial disappearance into the receiving slot 22 during upward or unlocking movement of the catch and thus the leading or rounded end 26 of the shank 12 provides an abutment to limit the application of an upward or unlatching force to the catch or holding 7 member 14. Lateral movement of the spring member 14 with respect to the shank 12 is limited by the generally flat guiding surfaces 57 (Fig. 2) of finger portions 23 and 24 of the shank.

Inassembling the latching device on the incubator, a predetermined number of spacing washers 58 (Fig. 2) are slipped over the inner or threaded end of the latch into juxtaposed relationship with shoulder or collar portion 16 and the threaded end is then fed through an opening 60 (Fig. '1) in supporting wall 62 of the incubator panel B. A lock washer 63 is then slipped over the end of the threaded end of the latching device, into abutting engagement with the inner side of supporting wall 62 of the incubator, and the nut or fastener 20 is threaded onto the threaded portion 18 to secure the fastening device to the incubator. It will be apparent that the pressure of the catch or spring member 14 on the mating or opposing portion of the door or closure A of the assembly can be varied by changing the number of spacing washers 58, thus changing the extent of protrusion of the latching device with respect to support B.

When the fastener is in assembled condition on the incubator and the door is moved or pivoted from the dotdash, open position illustrated in Fig. 1 to the full line closed position shown, the forwardly positioned head portion 44 of the spring member 14 of the fastening device engages the defining surfaces of opening 13 in closure door A, thereby moving the head 44 upwardly into the slot 22 in shank 12, and pennitting movement of the latter through opening 13 in the door. In this connection it will be noted that opening 13 is tapered at the inner extremities thereof, as at 61, to facilitate relative sliding movement between the defining surfaces of opening 13 and the sloped or diagonal lift portion 40 of head 44 of the spring member 14, and facilitate movement of the head portion out of interfering relationship with the door. When the door or closure A has been moved to fully closed position, the resiliency of spring member 14 snaps the head portion 44 of the latter into abutting, overlapped relationship with a mating portion of the door in the to securely hold the or rubber-like gasket to encircle the handto positively seal the door in closed position. A resilient 64 is usually provided on door A hole opening 66 in the incubator same.

As aforementioned the hook or catch section 38 of the head 44 of spring 14 extends generally diagonally rearwardly and it will be seen that any attempt to open the door A of the incubator without actuating the spring member 14 by means of lift section 40, will actually tend to force the head 44 of the spring into further or more extensive engagement with the mating portion of the door. In other words, the effective component of force applied by the door to the head portion 44 of the spring is in a downward and forward direction, i.e. generally perpendicular to the catch section 38, thus insuring that the tip or outer end of the spring 14 must be lifted to disengage the fastening device and permit opening of the door. The instant arrangement of latching device also permits much l g mo n of ead eng g m t f the vides a novel, fastening or latching device and one which is particularly beneficial in an incubator mechanism to hold the door or hand-hole door of the incubator assembly in closed position, and wherein the latching dethe latch, and because of the considerable length of the spring member 14 over which flexure may occur during operation of the device. In other words the magnitude of the length of body portion 34 and leg portion 30 of the spring due to the bent configuration thereof permits greater movement of the head portion 44 thereof and thus permits the catch portion 38 of the head of the spring to have a greater extension or overlap with the mating portion of the door A. This increased magnitude of body portion 34 and leg portion 30 of the spring also insures that the latter will be operating under low stress conditions during flexure of the spring to open the latching device. Thus the spring will have a much greater service life than prior art arrangements of latch actuating spring, and will not fail due to fatigue. Most of the flexure of spring member 14, during actuation of the latching device, occurs in the elongated body portion 34 thereof and its curved connection 32 with the downwardly extending portion of leg section 30, although this downward extending portion of the leg section 30 is flexed somewhat during actuation of the latching device. It will also be seen that the comparative shortness of lift portion 40 and of the downwardly and exteriorly extending portion of leg section 30 of the spring helps to insure that most of the flexure of the spring will occur in the elongated body portion 34 thereof.

The spring member 14 is preferably formed of stainless steel and the remainder of the parts of the latch are comprised of rust resistent metals such-as copper, nickel, chrome, etc., thereby eliminating corrosion of the latching device and resultant failure of operation, as so often occurs in prior art latching'mechanisms used with incubatorassemblies.

When it is desired to-unlock the closure or door A of the incubator, the head portion 44 of spring member 14 can be moved upwardly out of latching engagement with the mating, portion of the door (as shown in dotdash lines in Fig. 1) by pushing or applying pressure with afinger, such as the thumb of the operators hand, against diagonal abutment section 40 of the head 44, thereby flexing the body portion 34 and downwardly extending portion of leg section 30 of the spring member'and permitting withdrawal of the shank 12 from opening 13 in the door.

While the latching device has been illustrated in assembled position in the incubator so that the head or catch portion 44 thereof extends generally downwardly, it will be seen that the latch assembly may be easily rotated and thus set the head portion 44 to extend in any direction. The downwardly extending direction of the hook is the preferred one due to the ease with which the operators thumb can move the catch to inactive or inoperative position for opening of the closure door.

While the spring-like catch member 14 is shown as being secured to the stud by means of the pin member 50 and deformed portion 54, the leg section 30 of the catch member could be left straight and preferably disposed in passageway 28 in close or force fit relationship. In the latter event, the passageway 28 would preferably not extend completely through the abutment portion 16 of' thelatch, and the pin 50 and associated opening 48 could be eliminated. The catch member 14 would then be positively retained in assembly relationship on the stud by the bent configuration of the catch member in combination with the holding engagement of the latter by the deformed portions 56 of the shank 12 of the latch.

From the foregoing description and accompanying drawings it will be understood that the invention provice is comparatively simple in construction but is. much more positive in operation than prior-art mechanisms for accomplishing the same result, and wherein means is provided on the latching device to prevent overstressing of the catch spring member thereof and for properly positioning thecatch spring member in the latch assembly. The invention also provides a latching device of extremely durable construction and one which may be readily manipulated for unlatching the closed door on a support for movement of the door from closed position to open position.

The terms and expressions which have been used are terms of description and not of limitation and there is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and de-,

scribed or portions thereof, but it is recognizedv that various modifications are possible within the scope of the invention claimed.

We claim:

1. A latch for holding a closure pivotally mounted on a supporting part in shut position, said latch comprising on one end thereon a threaded portion, on the other end thereof a shank portion, and a shoulder portion disposed intermediate said shank and threaded portions, said shoulder and threaded portions being adaptedv for securing said latch to said supporting part, said shank portion being adapted to extend into an openinginto said closure and having a generally lengthwise extending slot therein, a yieldable member mounted on said shoulder portion. and extending outwardly therefrom, said yieldable member including a portion extending into said slot and a catch portion normally disposed exteriorly of said slot for holding engagement with a confronting: portion of said closure.

2. In a latch in accordance with claim 1 wherein said shank portion comprises means for limiting movement of'said yieldable member out of said slot in one direction.

3. In a latch for holding a closure pivotally mounted on a supporting part in closed position, said latch comprising a shoulder portion adapted for abutting engagement with said part and a forwardly projecting shank portion, said shank portion having a slot therein said shoulder portion having a transversely extending opening therein, a yieldable member mounted in. said last mentioned opening and extending into said slot, means for locking said yieldable member in said transverse opening, means on said yieldable member adapted for engagement with a mating portion of said closure to hold the latter in closed position, and thrust means on said yieldable member adapted for actuation by an. exv ternal force for flexing said yieldable member in a direc-' the shoulder portion, and a pin driven into said axial opening and engaging a portion of. said. yieldable member whereby said. yieldable member is deformed in the direction of movement of said pin to positively lock said yieldable member in assembled relationship on said latch.

5. In a latch in accordance with claim 3 wherein. said yieldable member comprises a leg portion adapted to be received in. said transverse opening, a body portion extending generally diagonally forwardly with respect to said shank portion from said leg portion and being received at its forward end in said slot, said second mentioned means being located on a head portion extending outwardly of said slot and connected to said body'portiom 6. In a latch in accordance with claim 4 wherein said pin projects outwardly of said one end of said latch.

7. In a fastening device comprising a threaded portion on one end thereof, a shank portion on the other end thereof and a'shoulder portion disposed intermediate said first mentioned portions, said shank portion having an axially extending slot therein, a yieldable holding member of bent configuration secured to said shoulder portion and projecting outwardly therefrom, said last mentioned -member being generally reversely bent to form a body portion extending diagonally into said slot,

said holding member including a head portion connected to said body portion, said head portion normally projecting outwardly of said slot and including an abutment for providing for flexure of said body portion and movement of said head portion into said slot upon application of a predetermined force to said abutment.

Brining Apr. 17, 1906 Pollock Oct. 5, 1954 

